Extensor digitorum

Muscle parts

None

Latin name

Musculus extensor digitorum

Latin muscle parts

None

Group

Antebrachial muscle – posterior compartment - lateral group

Etymology

In English this muscle’s name is the muscle that straightens the fingers. The word extensor comes from the Latin ex meaning “out from” and tendere meaning “to stretch.”The term digitorum is from the Latin digitus, which originally meant the “pointing thing,” a term that is similar to the Sanskrit word “dic” meaning to show or point out. Because we point with our fingers the term was applied to the fingers and then the toes.

Origin

Lateral epicondyle of humerus via the common extensor tendon

Insertion

Posterior surface of the phalanges via the extensor expansion

Action

Extension of the wrist and all digital joints

Nerve supply

Radial nerve (C7 and C8)

Blood supply

From proximal to distal, the belly of the muscle receives blood from the posterior interosseous artery and its recurrent interosseous branch and the perforating part of the anterior interosseous artery. The distal tendons of the muscle are supplied by branches from the dorsal carpal arch, dorsal metacarpal arteries, and dorsal digital arteries.